Effects of Switching from Timolol to Brimonidine in Prostaglandin Analog and Timolol Combination Therapy

To assess the efficacy and safety of switching from timolol 0.5% to brimonidine 0.1% in patients with glaucoma treated with a prostaglandin analog (PGA) and timolol combination.This prospective, open-label multicenter study enrolled patients with open-angle glaucoma or ocular hypertension who were being treated with a PGA and timolol. After baseline measurements, timolol was switched to brimonidine 0.1%, and patients were followed for 12 weeks. Patients visited at 4 and 12 weeks after switching. The main outcome measure was the change in intraocular pressure (IOP). For safety evaluations, hyperemia, formation of conjunctival follicles, superficial punctate keratopathy as a local side effect, blood pressure (BP), and heart rate (HR) were evaluated.One hundred seven patients participated in this study. Among them, 103 patients completed the study. The IOP values at baseline, 4 weeks, and 12 weeks after the transition were 15.7 ± 2.7, 14.3 ± 2.8, and 14.0 ± 2.8 mmHg, respectively. IOP was significantly reduced at 4 and 12 weeks compared with baseline (p0.001). There were no significant changes in hyperemia or follicle formation. The superficial punctate keratopathy score was significantly reduced at 12 weeks compared with baseline (p0.05). Systolic and diastolic BP values were significantly reduced and HR significantly increased after switching (p0.05).Switching from timolol 0.5% to brimonidine 0.1% may not change IOP in the combination use of timolol 0.5% and a PGA and was well tolerated by patients without severe ocular or systemic side effects.